New wrinkles in the Great American Pizza Story aren’t uncommon, but it nevertheless shook the pizza world to its core when, last week, a Chicago researcher named Peter Regas detailed new evidence that he says fundamentally changes the story of how pizza first arrived in New York — which is to say of how pizza first arrived in America.

Along with the aid of a bonafide pizza expert, we’ve created this guide to help you get to know the planet’s varied styles of pizza. From Neapolitan to Detroit-style, we’ve got you covered.

It’s not your Italian grandmother. A New York City feud over a tangy Sicilian slice could be heading to court.

Alongtime pizzaiolo at Prince Street Pizza, one of New York City’s truly great pizzerias, has opened his own joint, slinging Sicilian slices made from an original recipe that he claims he created. Now, his former business partner is threatening legal action, saying that recipe belongs to him, and the chef isn’t allowed to take it elsewhere.

While New Yorkers can certainly be parochial and protective of their home slice, they can also be open and accepting of different pizza points of view. Here is a look at the predominant forms of pizza found in New York City with information about how they developed over the years, and a glimpse at some of the more eclectic and disparate variations on the theme.